This invention relates generally to structural connector elements and, more particularly, to rigid locking connections between support members used in supporting grid systems.
While not limited thereto, the present invention is particularly adapted for use in ceiling tile supporting grid systems of the type comprising a plurality of parallel spaced main grid members and cross grid members extending transversely between the main grid members and having end portions insertable through said main grid members and interlocking therewith. In attempting to provide a strong, rigid tile supporting grid construction, various types of locking connectors have been proposed for these cross grid member end portions. A common expedient is to form resilient locking fingers struck out laterally from the body of the connector to provide a vertical abutting edge facing away from the leading end of the connector and adapted to engage behind the web of the transversely extending main grid member. Since the resilient locking finger must pass through the slot of the main grid member and is then snapped laterally outwardly out of the plane of the connector body, it is apparent that a slight clearance will exist between the vertical locking edge of the locking finger and the main grid member web adjacent the slot thereof. While this clearance between each intersecting pair of grid members may be minute, it is cumulative along the entire span of the grid supporting construction, resulting in a generally loose supporting grid system.
Also, a problem often is presented with such finger locking arrangements where building code specifications require a high pull-apart resistance in disengaging the cross grid members from the main grid members.